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On a virtual debian machine in VIRTUALBOX I type: ssh -R 2222:localhost:22 andrea@, to make reverse tunneling and allow remote machine to see debian desktop. on the remote machine (ubuntu) I've: ssh_exchange_identification: connection closed by remote host and connect to port 22: failed Can you help me please??

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migrated from Mar 18 '13 at 10:33

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I've already modified my hosts.allow file adding the line: SSHD: ALL but nothing, ssh server still refuses to make my day a good day. – user1703524 Mar 18 '13 at 9:02
Is the "remote machine(ubuntu)" also running in VirtualBox? What's the host OS, what kind of networking have you configured for the VMs? – tink Mar 18 '13 at 18:50

This happens to me, too. I am running Ubuntu 16.04 Server and I save the machine state before quitting. When I start it back up, I often get this error message when trying to connect, but then after about 15–20 seconds everything is ok again. My guess is that it has something to do with saving the machine state and then, upon starting again, the machine's having to update itself with the current network configuration, time, etc. before allowing new, valid connections.

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